Is there anyway to overcome the hide attribute - that is make them visible to my troops. AS it is now, They enter eg a camp (no walls) and surround the archers and crossbowmen and when they become visible en masse, the forces are defeated. Now the only thing I can do is surrender

Same when I am moving an army around, I get caught without walls.

Even with walls, if they send several battering rams at once, taking force out to attack them lets the invisible goblins in. And once even one is in, shutting gates does not stop the rest from entering.

A counter to the Goblin Hide is actually a counter to all Goblins. They are very weak to AoE.

If you had 1 bladestorm in the middle of that goblin horde you would wipe most them out with a well placed whirlwind or whatever the AoE is. I get them confused, but both the Elves and the Orcs have this type of AoE melee unit.

I've just started playing humans so I'm not sure what their counter horde unit / ability is.